Swinging scaffold



March 2, 1948, R. .-1.y LACKNER Y v 2,436,813

` swINGING scAFFoLJD Filed oct. 7, 1946 l 2 sheetssheet 1 IN1/EN TOR.Robo/,2 [Laczel RQJ. LACKNER SWINGING SCAFFOLD Filed 001;. `"f, 1946 2Sheets-Sheet 2 IN V EN TOR.

Patented Mar. 2,`1948 SWINGING SCAFFOLJ.)V

Rolph J.. Lackner, Richmond Hill, N. Y., assigner to Emma H.

Lackner, Richmond Hill, N. Y.

Application october 7, 194e, serial No. l101,701 g.

This invention relates to improvements in swinging scaffolds of thecharacter disclosed in my co-pending application led August 1, 1946,Serial No. 687,730.

Usually, the free ends of the ropes suspending the scaifold platform areeach knotted about the respective hooks of the lower pulley blocks and.are so tied in, vas it is called, for securing the platiorm at the leveldesired. However, the knots mentioned often become loosened or untied,for onereas'on or another, or are carelessly tied initially,l withconsequent disastrous results. Furthermore, repeated knotting of theropes Claims. (Cl. S04-19)A lfore unnecessary herein applicationpreviously identified, and it is there-` to' again go into all thedetails thereof. However, sufficient explanation will be made to renderthe present improvements clear.

Referring more particularly to Figure 1 of the drawings, I employ theusual platform Ill having tends to break the fibers thereof and thus pshortens the period of usefulness thereof.

The objects of the present invention therefore, in addition to theobjects set forth in my pending application mentioned, are-to provide aconstruction wherein the free ends of the ropes sus pending the scaioldplatform may be safely se cured Without knotting the ropes, wherein thefree ends of the ropes may be so secured without injury thereto, whereinrope clamps each having a fixed and movable jaw will be provided inconjunction with the suspending ropes, wherein the movable jaw may, bymeans of a locking mechanism therefor, be manually shifted to clamp thestrands of a rope between the jaws, when the movable jaw will be heldlooked in such position to forestall, in so far as possible, any elementof carelessness in securing the free ends of the ropes as well asprevent falling of the scaffold platform at either one end or the otherthereof should a strand of one of the ropes break, thus to avoid ensuingaccident to the workmen on the platform, and wherein said lockingmechanism will be so formed that should a strand of either rope break ata time when the strands of the ropes are released and the platform isbeing raised or lowered, the clamps will be automatically caused to gripsaidstrands and prevent the fall of either end of the platform.

Other and incidental objects of the invention will appear during thecourse of the following description, and in the drawings:

- Figure 1 is a front elevation of my improved scaffold.

Figure 2 is a perspective view of one of the rope clamps employed.

Figure 3 is a-planview of the clamp.

Figure 4 is an end elevation of the clamp.

Figure 5 is a section on the line 5-5 of Figure 3.

Figure 6 is a section on the line 6-6 of Figure 4.

rungs II supporting a iloor I2. Conventional stirrups i3 embrace theplatform and are provided at their upper ends with eyes I4 as well aswith the usualioops I5 which'latter removably receive a guard rail I5.Beams' I 'I'project-over the ,roof or' other portionoi the'bu'ildingagainst which the scaffold 'is erected, as will'be well understood, `anddetachably' connected therewith are upper pulley trained about lowerpulley blocks 20,'the usual hooks 2l of which latter are detachablyengaged through the eyes I4 of the stirrup's I3 for sup porting theplatform I0 suspended. Suitably ilxed to the blocks are rope clamps, now to be Y described, but as the parts seen at the right and left ofFigure 1 are the same, only a single block and associatedparts need betaken up'in detail.

Referring now more particularly to Figures 2 to 6 of the drawings, eachlof the rope clamps mentioned includes a shank 22 which may be integralwith the sheath of its supporting block 2E! or appropriately attachedthereto, and formed on the shank at its upper end is a yoke 23 belowr'which is a laterally extending fixed jaw 24 having spaced lingers 25.l

. Pivoted upon the yoke 23 'is a movable jaw 26 confronting the fixedjaw, and extending laterally from the movable jaw is an' arm 21 fromwhich rise lugs 28 fitting between the arms of said yoke. Extending frombetween the lugs 28 is an operating lever 29, and detachably connectingsaid lugs and the arm with the yoke 23 is a pivot bolt 30 mounting themovablel jaw 2t to rock on said yoke. Adjustable through the free end ofthe'arm 21 is a set screw 3l. n

Detachably fixed to the ends ofthe jaw 26 are fingers 32 which extendacross the ends of the jaw 24 and cooperate with the n'gers 25 topartition the space between the jaws. Thus, as seen in Figures 3 and 6,the 'strands of the coaoting rope i9 may notbecome entangled at' therope clamp.

The structure of the present invention is, in

Detachably fixed to the rung II atv the adjacent end of the platform I0is a collar 33, and extendring between said collar and the-v free end ofthe level' 2 8 is a lineally adjustable connecting rod 34 preferablyformedv of mating detachably' oonnected sections.

blocksl which receive ropes I9 As will now be seen, should a strand ofone of the ropes i9 break, the platform I0 will move down at theadjacent end thereof and so pull downwardly on that one of the levers 29connected thereto, with the result that the movable jaw 26 of theassociated rope clamp will be rocked toward the fixed jaw 24 of saidclamp to bind the strands of the rope between the jaws. Thus, theplatform will be automatically prevented from swinging to verticalposition. Further, as will be seen, the closing throw of the movable jaw26 may be roughly adjusted by lengthening or short-VV ening theconnecting rod 34, while a, finer adjust ment of said throw may be hadby turning the set screw 3|.

Associated with the movable jaw 26 is a locking mechanism therefor. Inthe present instance, I have shown the shank 22 bent near its upper endto provide a laterally extending yoke 35, and suitably fixed in themouth of said yoke is an end plate 36. However, the yoke may be formedas a separate part and attached to the shank, in which event the plate36 will not be necessary. Journaled through the outer end of the yokeand through said plate is a screw shaft 31 upon the outer end of whichis fixed a hand wheel 38, and screwed upon said shaft is a crossn head39 slidably fitting between the sides of the yoke. Thus, as the handwheel is turned, the crosshead will shift within the yoke. As best seenin Figure 6, said cross head is provided with aligned trunnions 40.

Depending from the arm 2l at the plane of the lugs 28 is a transverselug 4I which, as will be presently seen, serves as a lever, andextending through said lug is a removable pin 42. Extending between saidpin and the trunnions 49 of the crosshead 39 are links 43, and formed inthe forward ends of said links are slots 44 which slidably accommodatethe ends ofthe pin.

As will now be appreciated, the hand wheel 38 may, after the platform Ihas been raised to the desired level, be turned for shifting thecrosshead 39 outwardly in the yoke 35 and so rocking the movable jaw 26toward the fixed Yjaw 24 to active position binding the strands of thecoacting rope I9 between the jaws. Thus, the free end of the rope, alongwith the other strands thereof, will be safely secured between the jawswhile, also, the movable jaw will be locked in active position.Accidental release of the free end of the rope will thus be prevented.Furthermore, should one of the strands of the rope break, the platformI!) will be prevented from swinging down atY the adjacent end thereof.

By turning the hand wheel 38 in a direction opposite to that rstdescribed, the crosshead 39 may be shifted inwardly within the'yoke 35for releasing the movable jaw 26 so that the coacting rope -l9 will befree to be employed for either raising or lowering the platform I0. If,during either operation, one of the strands of the ropev should break,the adjacent end of the platform ID will start to move down, with theresult that the movable jaw 26 will, as previously described, beactuated by the lever 29 forl automatically swinging the movable jawtoward the fixed jaw 24 and binding the strands of the rope between thejaws. The platform will accordingly be prevented from falling. As themovable jaw is thus rocked, through the medium of the lever 29, towardthe fixed jaw, the slots 44 inthe links 43 will accommodate travel ofthe endsof the pin 42 relative to said links so that the movable jaw maybe freely actuated automatically.

Having thus described my invention, what I claim is:

1. A safety device for swinging scaffolds including a fixed jaw and amovable jaw disposed at opposite sides of the scaffold suspending ropeand normally free thereof, a plvoted lever movable upwardly away fromthe movable jaw independently thereof and downwardly to operativelycoact with said movable jawfor rocking the same toward the fixed jaw toclamp said rope therebetween, means rfor supporting said jaws and thelever from a, pulley block of the scaffold,

Va connection between the free end of said lever and an end of thescaffold platform whereby dropping of'said end of the platform willcause actuation of the movable jaw to grip the suspending rope betweensaid jaws, and locking mechanism for the movable jaw carried by saidmeans and operable to lock said movable jaw in position clamping therope between the jaws, said mechanism including an element operativelycoupled with the movable jaw and manually operablev to swing the movablejaw toward the xed jaw independently of said lever and clamp the ropebetween the jaws.

2. A safety device for swinging scaifolds including a fixed jaw and amovable jaw disposed at opposite sides of the scaffold suspending ropeand normally free thereof, a pivoted lever movable upwardly away fromthe movable jaw independently thereof and downwardly to operativelyeoact with said movable jaw for rocking the same toward the fixed jaw toclamp said rope therebe-j tween, means for supporting said jaws and thelever from a pulley block of the scaffold, a con nection between thefree end of said lever vand an end of the scaffold platform wherebydropping of said end of the platform will cause actuation of the movablejaw to grip the suspending rope between the jaws, locking mechanism forthe movable jaw carried by said means and operable to lock said movablejaw in position clamping the rope between the jaws, said mechanismincluding an element operatively' coupled with the movable jaw andmanually operable to swing the movable jaw toward the fixed jawindependently of said lever and clamp the rope between the jaws, and aconnection between said element and the mov# able jaw embodying means toaccommodate actuation of the movable jaw by said lever while the movablejaw is spaced from the fixed jaw to free said rope.

3. A safety device for swinging scaffolds including a fixed jaw and amovable jaw disposed at opposite sides of the scaffold suspending ropeand normally free thereof, a pivoted lever movable upwardly away fromthe movable jaw independently thereof and downwardly to operativelycoact with said movable jaw for rocking the same toward the xed jaw toclamp said rope therebetween, means for supporting said jaws and thelever from a pulley block of the scaffold, a connection between the freeend of said lever and an end of the scaffold platform whereby droppingof said end of the platform will causeactuation of the movable jaw togrip the suspending rope between said jaws, locking mechanism for theYInov-- able jaw carried by said means and-including a manuallyrotatable screw shaft, a crosshead screwed on said shaft and shiftableby turning the shaft, and a connection between said crosshead and themovable jaw operable as the crosshead is shifted for swinging themovable jaw toward the fixed jaw independently of said lever andclamping the rope between the jaws, l

4. A safety device for swinging scaffolds including a xed jaw oppositesides ofthe scaffold suspending rope and normally free thereof, apivoted lever movable upwardly away from the movable Jaw independentlythereof and downwardly to operatively coact with said movable jaw forrocking the same toward the xed jaw to clamp said rope therebetween,means for supporting said jaws and the lever from a pulley block of thescaifold, a connection between the free end of said lever and an end ofthe scaffold platform whereby dropping of said end of the platform willcause actuation of the movable jaw to grip the suspending rope betweensaid jaws, locking mechanism for the movable jaw carried by said meansand including a manually rotatable screw shaft, a `crosshead screwed onsaid shaft and shiftable by turning the shaft, and a connection betweensaid crosshead and the movable jaw operable as the crosshead is shiftedfor swinging the movable jaw toward the fixed jaw independently of saidlever and clamping the rope between the jaws, said last mentionedconnection embodying means to accommodate actuation of the movable vjawby said lever while the movable jaw is spaced from the fixed jaw to freesaid rope.

5. A safety device for Swinging scaffolds including a fixed jaw a'nd amovable jaw disposed at and a movable jaw disposed at t opposite sidesof the scaffold suspending rope and normally free thereof, a pivotedlever movable upwardly away from the movable Jaw'independentiy thereofand downwardly to operatively coact with said movable jaw for rocking,lthe same toward the fixed jaw to clamp said rope therebetween, meansincluding a shank for supporting said jaws from a pulley block of thescaiold, a connection between the free end of saidA lever and an end ofthe scaffold platform whereby dropping of said end of the platform willcause actuation of the movable law to grip the suspending rope betweensaid jaws, a yoke carried by said shank, a manually adjustable screwshaft journaled upon said yoke, a crosshead screwed on said shaft andshiftable in said yoke as said shaft is rotated, a lug carried by themovable jaw, a pin carried by said lug, and links connecting thecrosshead with said pin at opposite sides of said lug and operable asthe crosshead is shifted for swinging the movable jaw toward the xed jawindependently of said lever and clamping the rope between the jaws, saidlinks being provided with slots receiving the ends of the pin andadapted to accommodate actuation of the movable jaw yby said lever whilethe movable jaw is spaced from the fixed jaw to free said rope.

ROLPH J. LACKNER.

